Jim DeMint resigning from the Senate to run the Heritage Foundation

Mr. DeMint will leave his post as South Carolina's junior senator in early January to take control of the Washington think tank.

Sen. DeMint's departure means that South Carolina Governor Nikki Haley, a Republican, will name a successor, who will have to run in a special election in 2014. In that year, both Mr. DeMint's replacement and Sen. Lindsey Graham will be running for reelection in South Carolina.